In a patent application entitled Polymer Finishing Process filed on even date by George N. Foster and Hugh E. McGee under Ser. No. 625,933, a process was proposed whereby catalyst deactivator compounds, thermal oxidation stabilizer compounds, and general purpose additives were added sequentially to a polymer melt. The object of this process was to improve the stability of the polymer and avoid discoloration. While such a process is certainly advantageous, polymerization involving polar comonomers and free radical generators, as well as Ziegler-Natta catalysts, present an additional problem in that acidic products are formed from the degradation of the various materials involved in the polymerization. The identification of polymer impurity deactivators, useful in countering these degradation products, would enhance those polymer finishing processes based on polar comonomers and free radical generators.